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Emergency Diesel Generator Qualification, Site Acceptance, and Surveillance Testing 11. QUALIFICATION, SITE ACCEPTANCE 6. Comments on the relevance of this AND SURVEILLANCE TESTING material to EDG selection/operation. Learning Objectives NOTE: Principle design and application criteria for EDG units in nuclear power The primary objectives for this lesson are to plants are listed in Clause 4 and Table 1 of present the tests that EDGs are subjected IEEE 387-1995. Chapter 1 of this Manual to: (1) during their initial "type qualification" introduced the fundamental goal of 4000 for nuclear service, (2) by the EDG EDG starts and 6000 operating hours over supplier, upon installation at the site, to a service life of 40 years. Other important demonstrate compliance with the purchase design criteria include the maximum and contract, (3) as part of the licensee's pre- minimum temperatures and humidity to operational tests to verify performance and which equipment will be exposed, seismic develop baseline data, and (4) during response spectra, radiation, barometric regular surveillance runs by the licensee. A pressure (altitude), potential contamination typical surveillance run will be outlined, of combustion air or support systems by including the control of KW and KVAR load salt spray / sand / dust, the service water with the EDG connected to the grid. To quality and temperature, and also the effect reinforce this material, the lesson will then of potential events such as severe weather conclude with some comments about EDG and possible actuation of the fire protection selection, plus operational examples that system. The focus of this Chapter is on help explain the relevance of these tests to EDG testing but some of the above design actual operations. criteria are factors in the case histories discussed in other parts of this Manual. Upon completing this lesson, students will have a better understanding of: 11.1 EDG Type Qualification Tests for Nuclear Service 1. How EDGs are type-qualified for nuclear power plant service. In order for a diesel generator to be used as an on-site emergency standby power 2. Installation, break-in run, inspection, source at a nuclear power plant, it must first and full load run by the EDG supplier. be "type qualified" for that service by successfully passing rigorous performance 3. The licensee's pre-operational test tests and analyses to prove it can perform program to verify EDG performance its intended function. Regulatory Guide 1.9 and establish critical baseline data. (now Revision 4, March 2007) contains the basic requirement for that and IEEE 387 4. The licensee's ongoing surveillance (1995 edition) provides detailed guidance. testing of their diesel generators. Prior qualification of an EDG of similar design is permitted to be used to reduce 5. A typical EDG surveillance run by the the testing and analysis required. Analysis licensee, including control of KW and is most often used when testing is seen as KVAR loading when on the grid. impractical or unneeded. Rev 1/11 11-1 of 22 USNRC HRTD Emergency Diesel Generator Qualification, Site Acceptance, and Surveillance Testing The initial "type qualification tests" for 1. Carry load equal to continuous rated EDGs are listed and discussed in Clause 6 load for time required to achieve engine of IEEE 387-1995, "Standard Criteria for temperature equilibrium, followed by: Diesel-Generator Units Applied as Standby Power Supplies for Nuclear Power 2. Carry the short-time rated load for 2 Generating Stations." Diesel generator hours and the continuous rated load for qualification tests may be performed by the 22 hours. These different loads are manufacturer or by an independent third permitted to be applied in either order. party supplier. The latter arrangement is most likely due to the manufacturer of the 3. Complete a load rejection test at the engine-generator set not maintaining an short-time load rating. Speed increase approved 1O CFR 50 Appendix B quality shall be less than 75% of the difference assurance program. Usually, qualification between nominal speed and the over- is completed by the manufacturer, prior to speed trip set-point, or 15% over the delivery of the EDG units to the plant site. nominal (60Hz) RPM, whichever is less. In a few early 1970's vintage plants, part or all of the EDG type qualification testing was 4. Complete light/no-load test equal to the conducted on-site. This was because the design light load, for allowed duration. IEEE 387 type qualification tests were not (Follow with ≥50% load for ≥0.5 hour.) formally endorsed by Regulatory Guide 1.9 until after manufacture and delivery of the Start and Load Acceptance Tests: EDGs to those early nuclear plant sites. Modified qualification testing was agreed to This is a very intense and grueling portion by the licensees and performed on-site. of the qualification tests. It requires starting and loading an EDG, or group of EDGs of 11.1.1 Three Basic "Type Qualification" the type being qualified, to verity the Tests for Nuclear Service EDGs capability to start and accept load within the time permitted by the plant design basis. A The tests outlined in Clause 6 of IEEE 387- total of 100 starts are performed, with zero 1995 will be covered in more detail later in failures permitted. (Previous editions of this Chapter. The present discussion will this Standard required 300 starts, with no serve to introduce the three basic tests that more than 3 failures.) If multiple engines are used to verify the ability of an EDG to are used, to speed up the testing, each perform its design basis mission. They are: engine must be tested for Load Capability, and Margin (the latter test is discussed on Load Capability Tests: the next page). Additional test criteria can be found in Clause 6.2.2 of IEEE 387-1995. This is to demonstrate the EDG's ability to carry the following loads at rated power This effort can also be challenging to the factor, for the periods of time indicated, to test facility, as it is very labor intensive and successfully reject a heavy load, and also takes weeks (or even months) to complete, to operate at light load (or no load) as depending on any problems or failures. An specified by the manufacturer. overview of these tests follows: Rev 1/11 11-2 of 22 USNRC HRTD Emergency Diesel Generator Qualification, Site Acceptance, and Surveillance Testing 1. Start and achieve specified voltage and Margin Tests (transient conditions): frequency within the required time. This is a series of extra high stress tests 2. Immediately accept a single step load intended to demonstrate that the EDG has equal to or greater than 50% of the a performance safety margin for that plant's continuous kilowatt (KW) rating. design. It requires two or more loaded run tests applying loads greater than the most 3. At least 90 of these tests shall be with severe step load in the plant design profile, the EDG initially at warm-standby, with including step changes above a base load lube oil and water jacket temperatures (any steady point on the loading profile). being kept at or below the values The limiting case (worst case) step change recommended by the mfr. After load is over base load, as defined by the design applied, run until temperatures are load profile, shall be demonstrated. stabilized at normal levels for the load. "Worst case" is not necessarily the largest 4. At least 10 of these tests shall be with single step load, as the most severe step the engine at its normal operating may be a smaller load applied as the temperatures for the load ("hot start"). EDG's full-load capability is approached. However, a margin step load at least 10% 5. Any failure requires a design review, greater than the magnitude of the most corrective action, and continuation of severe single-step load within the load the tests until reaching 100 consecutive profile is deemed sufficient for the margin starts without failure. test. The criteria for margin tests are: NOTE: Allowance is made to disregard any 1. Demonstrate the ability of the generator, test start categorized below, and resume exciter, and automatic voltage regulator the test sequence without penalty: to accept the margin test load (usually a low power factor, high inrush starting A. Unsuccessful attempts that are clearly current to a pump motor), without the result of operator error. generator instability resulting in voltage collapse or inability of the voltage to B. Tests performed to verify a scheduled recover. normal maintenance procedure. 2. Demonstrate the ability of the engine C. Tests performed for troubleshooting and its speed-regulating governor to purposes, defined as such in advance. accept that load without stalling, and to recover to normal operating speed. D. Successful start attempts which were terminated intentionally, without loading. NOTE: Frequency and voltage excursions recorded during this test may exceed those E. Failure of any temporary service system values specified for the plant design load, or any temporary hookup that will not be as this test load should never be reached in part of the permanent EDG installation. the course of normal emergency service. Rev 1/11 11-3 of 22 USNRC HRTD Emergency Diesel Generator Qualification, Site Acceptance, and Surveillance Testing 11.1.2 Additional EDG Evaluation by seismic event. Seismic testing shall be Test or Analyses followed by functional testing to verify the relevant principle design criteria covered in Aging of Components and Assemblies: Clause 4 of IEEE 387-1995. Clause 6 of IEEE 387-1995 introduced 11.1.3 Analysis/Test of Design Change comprehensive evaluation of ageing over to EDG Previously Qualified the design life of the EDG plant.

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